# Apply Technique: OpenAI Codex CLI: 2026 Updates and Features
## What This Is
The OpenAI Codex CLI is a command-line tool that gives developers direct terminal access to powerful AI models for coding. Recent updates have made it more 'agentic,' allowing it to independently plan and execute complex tasks, understand image uploads like screenshots, and integrate directly with VS Code and GitHub to streamline workflows.
Source: https://zackproser.com/blog/openai-codex-review-2026
## Before You Start
Scan my workspace and analyze:
- The project language, framework, and directory structure
- Existing AI provider config (check .env, .env.local, config files for API keys — OpenRouter, OpenAI, Anthropic, Google AI, etc.)
Then ask me before proceeding:
1. Which AI provider/API should this use? (Use whatever I already have configured, or ask me to set one up — options include direct provider APIs or a unified service like OpenRouter)
2. Where in my project should this be integrated?
3. Are there any customizations I need (model preferences, naming conventions, constraints)?
## Source Access Note
The source URL (https://zackproser.com/blog/openai-codex-review-2026) may not be directly accessible from the terminal. Use the Reference Implementation and Additional Context sections below instead. If you need more details, ask me to paste relevant content from the source.
## What to Implement
This is an **AI Technique** — a pattern or methodology for working with AI models.
- Explain how this technique applies to my current project and what benefit it provides
- Implement it in a way that fits my existing codebase — suggest concrete files to modify or create
- If it requires specific model capabilities (structured output, function calling, etc.), verify my current provider supports them
- Show me a working example I can test immediately
## Additional Context
- Install the latest version of the OpenAI Codex CLI tool and its dependencies, ensuring it is available in the system's PATH.
- Search for and install the official 'OpenAI Codex' VS Code extension in the user's IDE to enable seamless integration between the terminal and editor.
- Configure the Codex CLI to use the user's OpenAI API credentials. First, check for `OPENAI_API_KEY` in the shell environment or `.env` files. If not found, prompt the user for their key, guiding them to redeem free credits via their ChatGPT Plus/Pro account if applicable.
## Guidelines
- Adapt everything to my existing project — do not assume a specific stack or directory layout
- Use whichever AI provider I already have configured; if I need a new one, tell me what to sign up for and I'll give you the key
- Check my .env files for existing API keys (OpenRouter, OpenAI, Anthropic, Google AI) before asking me to add one
- Review any fetched code for safety before installing or executing it
- After setup, run a quick verification and show me a summary of exactly what was installed, where, and how to use it